Magnetostrictive wired storage



Nov. 6, 1962 B. JACKS 3,063,037

MAGNETOSTRICTIVE WIRED STORAGE Original Filed Aug. 26, 1957 INVENTOR.BASI L JACKS United States Patent O 3,063,037 MAGNETOSTRICTIVE WIREDSTORAGE Basil Jacks, East Meadow, N.Y., assiguor to American Bosch ArmaCorporation, a corporation of New York Continuation of application Ser.No. 680,079, Aug. 26, 1957. This application Nov. 4, 1959, Ser. No.%50,879 6 Claims. (CI. 340-473) The present invention relates to storagedevices for digital computers and has particular reference tomagnetostrictive storage.

This application is a continuation of my application Serial Number680,079, filed August 26, 1957, now abandoned.

A constant rnagnetic field is provided for each coil by a smallpermanent magnet adjacent thereto, or by some other convenient means.

The present invention is a magnetostrictive storage wherein a number ofwords of digital information may be stored using only one set of outputcoils and a magnetostrictive wire, such as nickel, and input coil foreach word to be stored. In a preferred embodiment, the magnetostrictivewire is threaded through each pickofi coil from which a pulse isdesired, and around each coil from which no output is desired.

When the information stored by a particular magnetostrictive wire isrequired, the input coil for that wire is energized With a pulse, andthe desired information appears at the terminals of the series connectedpickoif coils as a series of pulses representing a digital number inserial form.

In an alternative arrangement, the magnetostrictive wires do notactually pass through the pickof coils, but are situated close enough tothe coil to create a change in the reluctance of the magnetic circuitthrough the coil whenever the wire is stressed.

For a more complete 'Understanding of the invention, reference may behad to the accompanying diagrams, in which,

FIG. 1 shows the magnetostrictive storage according to the presentinvention; and

FIG. 2 is a modification of FIG. l.

Referring to FIG. 1 of the drawings, a number stored by the apparatusshown is to be made available in binarial form upon energization of coil12a at the terminal 22 with which the output coils 13, 14, `15, 16 areconnected in series. For example, if the number eleven which correspondsto 1011 in binarial form is to be stored, a wire Ma of magnetostrictivematerial, such as nickel, spans the open area of a frarne 11 and isthreaded through each of the coils 12, 13, `14, 16 and around coil 15.The coil 12a is the input coil which is energized by a pulse at a giveninstant to produce a temporary magnetc field in the coil 12a and,thereby, to cause Creation of a compression or stress in the wire lilaat the position of coil 12a. This Stress spreads out from coil 12a inboth directions as a compression wave, one wave being absorbed by theacoustic clamping material 17 at one end of the wire 10, and the othercompression Wave passing successively through each of the pickotf coils13, 14, around coil 15, through coil 16 and finally being absorbed bythe clamping material 17 at the other end of the wire.- The dampngmaterial 17, which may be rubber for example, prevents reflection of thewave from the ends of the wire wa.

A separate bar magnet 18, 19, 21), 21 is placed adjacent each of therespective output coils 13, 14, and 16. As the compression wave in wire10 passes through the coil 13, the permeability of the magnetic circuitthrough the coil 13 changes whence the magnetic lines of flux frommagnet 18 linking coil 13 change accordingly. The variation of themagnetic flux through the coil 13 causes a positive pulse to appear atthe terminals of the coil 13. The term positive pulse includes amomentry voltage having a single positive peak which may or may not bepreceded and followed by lesser negative peaks. The term positive" ischosen for illustration, and in practice the pulse may be eitherpositive or negative with respect to a reference point on the circuit.Similarly, as the compression wave passes through each of the coils 14and `16 a positive pulse appears at the terminals of that coil. As thewave passes by coil 15, however, the efiect in the permeability of thecoil 15 is small Compared to the efiect on the others so thatpractically no pulse is obtained across coil 15.

Therefore, if the lowest order digit is represented by the output ofcoil 13, there appears a train of pulses at terminals 22 which isrepresentative of the binarial number 1011.

It Will be seen that the wires lila and wb are threaded through theirown input coils `12a and 121 respectively and through each of thoseoutput coils 13, 14, 15, 16 from which a positive pulse is desired andaround each of those coils 13, 14, 15, 16 from which a positive pulse isnot desired.

The wire lila is guided around the various pegs 23 so as to keep thesame length of wire lila between the planes of successive coils 13, 14,15, 16 in order to maintain the time interval between the pulses in theoutput signal at terminals 22 at the constant desired amount.

A second magnetostrictive wire ltlb is shown threaded through its inputwinding `12b around each of the coils 13, 14 through coil 15 and aroundcoil 16. Upon momentary energization of coil 1 2b, a serialrepresentation of the binary number 0100 is made available at terminals22. Thus, for any desired output at terminals 22, the magnetostrictivewire is threaded through and around the appropriate coils. As manyadditional numbers as desired may be stored simply by adding an inputcoil and a magnetostrictive wire for each number.

' FIG. 2 shows an alternative embodiment wherein a magnetostrictivestrip lila is merely positioned adjacent to the output coils rather thanbeing threaded therethrough. The coils 13, 14, 15 and 16 lie in ahorizontal plane, with the biasing magnets 18, 19, 20, 21 positionedabove the re spective coils and the magnetostrictive strip lilapositioned below the coils. The strip lt a is guided around the pegs 23,so as to be close to those coils 13, 14 and 16 from which a pulse isdesired and at a distance from those coils 15 from which a pulse is notdesired. The coils 13, 14, 15 and 16 are connected in series with theterminals 22 to produce at terminals 22 a serial binary representationof the number eleven, as in the prior examples.

In this embodment, the voltages induced in each of the coils 13, 14, 15,16 are all in the same direction, for example positive, but of twodistinct levels. The voltage induced in windings 13, 14 and 16 is muchgreater than that induced in winding 15. The output device connected tothe terminals 22, thcrefore, must be capable of distinguishing betweentwo levels of positive pulses. Although FIG. 1 shows the strip 10` asbeing located in a plane substantally perpendicular to the plane of thecoils, the strip 10a may be guided in a plane arallel to the plane ofthe coils if so desired. The schema of FIG. 2 allows for ease ofConstruction since the magnetostrictive wire need not be threadedthrough the coils.

Referring again to FIG. 1, it will be seen that the pulses to the inputcoils 12a, 12b, and others not shown, must be separated in time by anamount sufiicent to allow the compression wave in the firstmagnetostrictive wire to pass by the last coil 16 before the compressionwave on the next wire enters the first coil 13. In operation, thenumbers stored by the wires ma, 10b etc., not shown, can

be extracted only one at 'a time, but in any desired sequence.

Many modifications of the particular embodiments disclosed will occur tothose active in the art. For example, it will be seen that the outputcoils 13, 14, 15, 16 can be connected in parallel with terminals 22instead of in series With the terminals 22. Also, a magnet may be placeopposite the input coils as well as the output coils for improvedoperation. It is contemplated, too, that the magnetostrictive elementmay be a ribbon, strip or any other form of a long thin element, broadlyformed a magnetostrictive wire in the disclosure.

1 claim:

1. In a device of the character described, a support, an input coil infixed relation with said support, a plurality of output coils in fixedrelation with said support and said input coil, a magnet adjacent eachoutput coil, a magnetostrictive member threaded through said input coiland certain of said output coils and around others of said output coilsand connected adjacent its opposite ends to said support, and electricconnections between said output coils for connecting said coils wherebyan electrical signal is induced only in those coils through which themember is threaded.

2. In a device of the character described, a support, a plurality ofinput coils in fixed relation with said support, a plurality of outputcoils in fixed relation with said support and said input coils, a magnetadjacent each output coil for providing a magnetic fiux through eachoutput coil, a magnetostrictive member threaded through each of saidinput coils and said members being threaded through certain of saidoutput coils and around others of said output coils and connectedadjacent their opposite ends to said support and electric connectionsbetween said output coils for connecting said coils.

'3. In a device of the character described, a support, a plurality ofinput coils in fixed relation with said support, a plurality of outputcoils in fixed relation with said support and said input coils, a magnetadjacent each output coil for providing a magnetic flux through eachoutput coil, a separate magnetostrictive member threaded through each ofsaid input coils and said members being threaded through certain of saidoutput coils and around others of said output coils and connectedadjacent their opposite ends to said support and electric connectionsbetween said output coils for connecting said coils.

4. In a device of the character described, a support, an input coil infixed relation with said support, a plurality of output coils in fixedrelation with said support and said input coil, a magnet adjacent eachoutput coil, a magnetostrictive member threaded through said input coiland certain of said output coils and around others of said output coilsand connected adjacent its opposite ends to said support and electricconnections between said output coils for connecting said coils, thelength of said magnetostrictive member between successive output coilsbeing substanti-ally equal.

5. In a device of the character described, a support, a plurality ofinput coils in fixed relation With said support, a plurality of outputcoils in fixed relation with said support and said input coils, a magnetadjacent each output coil for providing a magnetic fiux through eachoutput coil, a magnetostrictive member threaded through each of saidinput coils and said members being threaded through certain of saidoutput coils and around others of said output coils and connectedadjacent their opposite ends to said support and electric connectionsbetween said output coils for connecting said coils, the length of saidmagnetostrictive member between successive output coils beingsubstantially equal.

6. In a device of the character described, a support, a plurality ofinput coils in fixed relation with said support, a plurality of outputcoils in fixed relation with said support and said input coils, a magnetadjacent each output coil for providing a magnetic flux through eachoutput coil, a magnetostrictive member threaded through each of saidinput coils and said members being in varying relation with certain ofsaid output coils for inducing voltages in certain of said coils.

References Cited in the file of this patent UNITED STATES PATENTS

